Traditionally answering machines comprise units which can be connected to a telephone line and which include memory for storing audio messages. In many examples these units are integrated with a telephone or wireless telephone base station. Such units have typically had a small number of buttons which are used to control the device and a screen (e.g. an LCD screen or a seven-segment display) to indicate the number of messages received. The playback of messages may be triggered using the buttons on the unit, or messages may be played back remotely where playback is triggered by detection of tones produced by dialing a number sequence. Such machines play the messages in the order that they have been received (i.e. oldest message first) and the identity of the caller or the length of the message is not known until the message is played back.
More recently, network implemented answering machines have become popular. Here the audio messages (also referred to as voice messages or voicemail) are stored within the telephone network (e.g. by a network operator) or within an exchange (e.g. within a company or organization) and the messages are accessed using a short-code dialed from a user's telephone (e.g. by dialing 5000) or by pressing a dedicated key on the telephone. Control of the answering machine may be via an interactive voice response (IVR) system. Again messages are played back in the order that they have been received and the identity of the caller and length of message may not be known until the message is played back. In some examples, however, the telephone number of the caller may be identified prior to playback of a particular message (e.g. through an audible message saying “Message received from 01234-567891 at 10.35 am”) or where the call is initiated within the same local exchange (i.e. within the same company), the caller may be identified (e.g. “Message received from John Smith at 10.57 am”).
Computer based answering machines have also been developed. In some cases these are standalone applications which record the calls and provide a graphical user interface through which details of the calls are displayed or in other examples these provide a user interface to a network implemented answering machine (e.g. when implemented on an exchange within an enterprise). In all cases, the user interface provides an email inbox style view showing a list of calls received in the order that they were received and in some examples, details of the name/number of the caller and the length of the call may also be displayed.